When a new tag is created on the main site, you get a warning before you can continue - this prevents creation of a tag by mistake. This was implemented as a result of this feature request: Warning ...

MathJax redisplay is very slow in the preview pane while editing answers in closed questions. Redisplay that normally happens in under a second can take up to $5$ times longer.
Not too infrequently ...

I've just flagged the question Indefinite integration $\int\frac{(2x^2)}{2xcos(2x)+(x^2-1)(sin(2x))}$ as a possible duplicate of another question posted by the same user. In the link text, a strange ...

I have encountered the following issue looking at my profile, see it in the photo.
This also happens if I change the browser or log off from my account or even if I check from my phone, and it also ...

I'm seeing something odd with the inline MathJax rendering on the MathJax basic tutorial.
There are 15 items in a numbered list in the tutorial. For items 1 to 5 (and also the first part of item 6) ...

Recently, I tried to start a bounty for two of my questions. But the error message "Unable to load popup -please try again" appears every time I start the bounty.
I don't know whether it is a error ...

On my profile page (and I'm sure yours as well), in the Top Posts section, the active tab ('Questions' or 'Answers') isn't readable because it's white-on-white:
On Meta, the selected tab is readable (...

An answer today caught my attention: https://math.stackexchange.com/a/2185406/62967
Here's an image of what I see with Safari 10.0.3 (with Firefox 52.0 it's the same):
The link in the spoiler is not ...

Sometimes if somebody edits the MathJax part of a question or answer MathJax breaks down in the revision history, creating italics and messing up formatting so that its really hard to see what changed....

I was just trying to procrastinate a bit of work, so I figured I'll check the review queue. This came up:
https://math.stackexchange.com/review/close/571044
It is a closing vote review of a question ...

This question was (rightly) closed as an exact duplicate: https://math.stackexchange.com/questions/1717381. (If I'm not mistaken, only moderators can do that.) The message at the top differs from the ...

Is there any way to retract a flag that has been cast accidentally and the post has not undergone any change after the flagging?
I saw this post on Retracting flags and that the feature request was ...

MathOverflow recently received a brand-new toy: a citation helper that adds a new button to the post editor to allow references to journal articles (and more?) to be added to posts quicker and easier.
...

Many questions by new users end up closed as duplicates or for another reason related to the lack of familiarity with the site. I won't go into details; they are much discussed.
I propose to enable ...

Below are a couple of screenshots take while using the Stack Exchange Android app. As you can see, each has [Math Processing Errors] (although not every MathJax instance brings up this error). When I'...

Supposedly I just earned this privilege. I clicked on the link and it took me to a page that lists a whole bunch of other privileges but not "see reduced ads". It's not like this website is brimming ...

I was trying to put a bounty on this old question of mine. I know there are some circumstances where bounties of certain amounts cannot be placed, see here, but this does not seem to be one of those ...

In this section of the FAQ the link "Writing the perfect question by Jon Skeet" is broken. I am unsure as to who handles these things, and even if I should be posting this here. I'm not that familiar ...

I noticed two answers that arguably should have been deleted from the review queue (Exhibits A and B; see also Exhibit C given by dustin in the comments, and there are probably many others as well).
...